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Seroepidemiology of Leptospira interrogans Infection in Ruminants of Lorestan Province: A Cross-Sectional Study
2020
Maleki, Shahram | Zakian, Amir | Abdollahpour, Gholamreza
BACKGROUND: Leptospirosis is a common bacterial disease in humans and livestock, which leads to reduced production and reproductive disorders in ruminants and also causes major economic losses to villagers and farmers. OBJECTIVES: The purpose of this study was to investigate the seroprevalence of different Leptospira interrogans serovars in ruminants population of Lorestan province and assess the role of environmental and host factors on the severity of the serological infection. METHODS: For this purpose, referring to livestock and sheep and goat flocks in different cities of Lorestan province, 691 blood samples were collected including 258 sheep, 195 goats and 238 cows, and then, the point of infection with seven different serovars of Leptospira interogans was assessed using microscopic agglutination test. Hosting factors such as age, gender and also environmental factors including geographical area, rainfall, temperature, relative humidity and altitude of sampling area from the sea level were recorded, and their probable role in the seroprevalence was statistically analyzed. RESULTS: Results of this study showed that the overall prevalence of leptospirosis in cattle, sheep, and goats examined in the Lorestan province was 26.05 % (95 % CI: 19.7-31.23), 22.48 % (95 % CI: 16.95-25.16) and 14.87% (95 % CI: 9.37-20.36), respectively. There was no statistically significant (p < /em>>0.05) difference from the point of age groups and sexes. The most prevalent contaminant serovars for cows, sheep, and goats with seropositive reaction against leptospira were grippotyphosa (41.93%), canicola (32.76%) and canicola (48.27 %), respectively. The results showed environmental factors including relative humidity (p < /em>=0.02), annual rainfall (p < /em>=0.001) and altitude from the sea level of sampling location (p < /em>=0.03) have a significant effect but the annual temperature does not have a significant effect (p < /em><0.05) on the seroprevalence of Leptospira. Also, more positive reactive animals in the eastern and western areas of Lorestan province were found (p < /em>>0.05). CONCLUSIONS: Leptospirosis is endemic in livestock population of Lorestan province and environmental factors play a significant role in the severity of infection, which increases the need for attention to the geographical areas at risk.
Afficher plus [+] Moins [-]Detection of white sturgeon iridovirus (WSIV) in wild sturgeons (Actinopterygii: Acipenseriformes: Acipenseridae) in Poland
2020
Hofsoe-Oppermann, Paulina | Kiełpińska, Jolanta | Panicz, Remigiusz | Bergmann, Sven M.
White sturgeon iridovirus (WSIV) disease is caused by a virus of the eponymous family and is mostly triggered by stressful environmental conditions, i.e. high rearing density, excessive handling, or temporary loss of water. The aim of this study was to develop the most effective diagnostic method for quick and efficient confirmation or exclusion of the presence of WSIV. A total of 42 samples (spleen, gills, intestine, skin, kidney, and brain) were collected from eight sturgeon (Acipenser gueldenstaedtii and A. oxyrinchus) aged ≤5+ farmed or caught between 2010 and 2014 in open waters (Dąbie Lake and Szczecin Lagoon). They were tested for WSIV presence using conventional PCR, qPCR, and in situ hybridisation (ISH). In gross examination, all fish appeared to be healthy. Neither species showed clinical signs typical of WSIV infection. In the majority of cases, fragments of iridoviral DNA were found using molecular methods in the kidneys, and also in the liver, gills, and skin. The detection rate using ISH was 47.37% and most commonly the brain and kidney tissues were positive. The most efficient of the methods used was real-time PCR, with 100% effectiveness in detection of WSIV DNA. The study demonstrates the capabilities for WSIV diagnosis available to sturgeon farmers and water administrators, indicating useful methods of adequate sensitivity as well as organs to sample in order to achieve the highest probability of viral detection.
Afficher plus [+] Moins [-]African swine fever virus – persistence in different environmental conditions and the possibility of its indirect transmission
2019
Mazur-Panasiuk, Natalia | Żmudzki, Jacek | Woźniakowski, Grzegorz
Since 2007, African swine fever (ASF) has posed a serious threat to the European swine industry. In Poland, the numbers of reported outbreaks in pigs and affected areas grow every year. In 2018, the disease was noted in Western Europe, in Belgium specifically, where several hundred infected wild boars have been detected so far. In 2018, the virus unexpectedly emerged in pig holdings in eastern China, northern Mongolia, Vietnam, and Cambodia, causing worldwide concern about its further spread. Since there is still no vaccine available, the only approach to control the disease is biosecurity. Identification of potential sources of the virus is extremely important in light of its phenomenal survivability. The review summarises the current knowledge about ASFV survivability and resistance to environmental conditions, and discusses the role of indirect contact in spreading the disease.
Afficher plus [+] Moins [-]Malignant catarrhal fever in cattle in the Irkutsk Region
2020
Zakharova, Olga | Toropova, Nadezhda | Burova, Olga | Titov, Ilya | Meltsov, Ivan | Blokhin, Andrey
Malignant catarrhal fever (MCF) is a rare, under-explored lethal viral infection of cattle with gammaherpesvirus aetiological agents. Most often, the disease occurs on farms where cattle and sheep are kept together. However, other trigger mechanisms and environmental factors contribute. This study investigates the causation of MCF. An outbreak of MCF occurred in June - August 2017 in Kharchev village in Irkutsk Oblast, Russia. In this paper, we provide epidemiological (sanitary status of pastures, watering places, and premises) and weather data during the outbreak, and descriptions of the clinical signs and post-mortem changes in cattle. The virus was detected and isolated from pathological material samples and identified by molecular methods. Extreme weather conditions, mixed-herd cattle and sheep farming, and unsatisfactory feed quality contributed to the outbreak. A virus related to herpesvirus OvHV2 was isolated and typed (MCF/Irkutsk/2017). Phylogenetic analysis showed its close genetic relationship to isolates from cattle and sheep in Germany, USA, and the Netherlands. Sporadic outbreaks of MCF caused by biotic and abiotic factors together are typical for the Russian Federation, and the Irkutsk outbreak epitomised this. Temperature anomalies caused pasture depletion, resulting in feed and water deficiency for grazing animals and dehydration and acidosis. Heat stress in animals ultimately led to the occurrence of MCF in the herd.
Afficher plus [+] Moins [-]Factors associated with the development of equine degenerative myeloencephalopathy
1990
Dill, S.G. | Correa, M.T. | Erb, H.N. | DeLahunta, A. | Kallfelz, F.A. | Waldron, C.
A case-control study was done to identify factors associated with the development of equine degenerative myeloencephalopathy (EDM). Questionnaires were mailed to the owners of 146 horses admitted to the New York State College of Veterinary Medicine between November 1978 and June 1987 and diagnosed as having EDM by histologic examination. Questionnaires also were sent to owners of 402 clinically normal horses admitted to the college during the same period. Data were compared between the EDM-affected and control groups (56 and 179 questionnaires returned, respectively). Risk factors identified included the use of insecticide applied to foals, exposure of foals to wood preservatives, and foals frequently spending time on dirt lots while outside. Foals spending time outside on green pastures was a protective factor. Foals from dams that had had an EDM-affected foal were at higher risk of developing EDM than were foals from other dams.
Afficher plus [+] Moins [-]Association between thermal environment and Salmonella in fecal samples from dairy cattle in midwestern United States
2016
Likavec, Tasha | Pires, Alda F. A. | Funk, Julie A.
The objective of this study was to describe the association between thermal measures in the barn environment (pen temperature and humidity) and fecal shedding of Salmonella in dairy cattle. A repeated cross-sectional study was conducted within a commercial dairy herd located in the midwestern United States. Five pooled fecal samples were collected monthly from each pen for 9 mo and submitted for microbiological culture. Negative binomial regression methods were used to test the association [incidence rate ratio (IRR)] between Salmonella pen status (the count of Salmonella-positive pools) and thermal environmental parameters [average temperature and temperature humidity index (THI)] for 3 time periods (48 h, 72 h, and 1 wk) before fecal sampling. Salmonella was cultured from 10.8% [39/360; 95% confidence interval (CI): 7.8% to 14.5%] of pooled samples. The highest proportion of positive pools occurred in August. The IRR ranged from 1.26 (95% CI: 1.15 to 1.39, THI 1 wk) to 4.5 (95% CI: 2.13 to 9.51, heat exposure 1 wk) across all thermal parameters and lag time periods measured. For example, the incidence rate of Salmonella-positive pools increased by 54% for every 5°C increment in average temperature (IRR = 1.54; 95% CI: 1.29 to 1.85) and 29% for every 5-unit increase in THI (IRR = 1.29; 95% CI: 1.16 to 1.42) during the 72 h before sampling. The incidence rate ratio for pens exposed to higher temperatures (> 25°C) was 4.5 times (95% CI: 2.13 to 9.51) the incidence rate ratio for pens exposed to temperatures < 25°C in the 72 h before sampling. Likewise, the incidence rate ratio for pens exposed to THI > 70 was 4.23 times greater (95% CI: 2.1 to 8.28) than when the THI was < 70 in the 72 h before sampling. An association was found between the thermal environment and Salmonella shedding in dairy cattle. Further research is warranted in order to fully understand the component risks associated with the summer season and increased Salmonella shedding.
Afficher plus [+] Moins [-]Histopathologic features, environmental factors, and serum estrogen, progesterone, and prolactin values associated with ovarian phase and inflammatory uterine disease in cats
1991
Lawler, D.F. | Evans, R.H. | Reimers, T.J. | Colby, E.D. | Monti, K.L.
Forty-four female American Shorthair cats with inflammatory uterine disease or infertility were evaluated. Data collected included age, month of diagnosis, housing, reproductive history, results of bacteriologic culture of uterine specimens, serum concentrations of estrogen, progesterone, and prolactin and histopathologic features of the ovaries and uterus. Histologically, the ovaries of 19 cats were dominated by active or cystic follicles, whereas 25 cats had luteal-phase ovaries. Of the 25 cats with active corpora lutea, 20 had either recently weaned litters (n = 11) without subsequent exposure to a male cat, or had been housed individually for lengthy periods (n = 9). The finding of active corpora lutea under these circumstances indicates that in queens, ovulation may occur by mechanisms not involving coitus. Prominent, active corpora lutea on the ovaries were associated with adenomatotic proliferative changes in the superficial and glandular epithelium of the uterus and with myometrial hyperplasia, compared with the uterus of cats with follicular ovaries (P < 0.01). Serum progesterone concentration greater than or equal to 1.87 ng/ml was consistently associated with luteal-phase ovaries. Serum progesterone values less than or equal to 0.15 ng/ml were consistently associated with follicular-phase ovaries. Escherichia coli was the organism most commonly isolated from uterine contents.
Afficher plus [+] Moins [-]Measurements of the radiographic cardiac silhouette of ospreys (Pandion haliaetus)
2019
Woo, Krystal M. T. | Barron, Grace H. | Daugherty, Allison L. | Woo, Jennifer M. P. | Kehoe, Spencer P. | Aguilar, Laura A. B. | Cavanaugh, Sarah M.
OBJECTIVE To evaluate and report measurements of the radiographic cardiac silhouette of healthy juvenile and adult ospreys (Pandion haliaetus). ANIMALS 54 ospreys (22 adults, 19 juveniles, and 13 birds of undetermined age) without clinical signs of cardiac disease and with adequate ventrodorsal radiographic images for cardiac silhouette assessment. PROCEDURES Radiographs of ospreys were assessed to determine cardiac width at the widest point as well as sternal width and thoracic width at the same level. Two-way mixed-effects models were used to evaluate interrater reliability for mean rating. Multivariable linear regression analysis was used to create predictive models of cardiac width and to establish a theoretical reference range for healthy ospreys. RESULTS Cardiac width of healthy ospreys was approximately 90% to 92% of sternal width and 67% to 69% of thoracic width. Both sternal width and thoracic width were significant predictors of cardiac width in independent predictive models as well as in a combined model after controlling for age. Thirty-four of 41 (83%) measured cardiac widths were within the theoretical reference range. CONCLUSIONS AND CLINICAL RELEVANCE Ospreys are sentinels used in monitoring environmental health. Environmental factors may have an impact on the cardiac health of ospreys, but reference values for healthy ospreys have not been established for use in assessing cardiomegaly in this species. The radiographic ratios and predictive model obtained in this study may be useful for objective evaluation of cardiomegaly in ospreys.
Afficher plus [+] Moins [-]Evaluation of a point-of-care glucose and β-hydroxybutyrate meter operated in various environmental conditions in prepartum and postpartum sheep
2013
Hornig, Katlin J. | Byers, Stacey R. | Callan, Robert J. | Holt, Timothy | Field, Megan | Han, Hyungchul
Objective-To compare β-hydroxybutyrate (BHB) and glucose concentrations measured with a dual-purpose point-of-care (POC) meter designed for use in humans and a laboratory biochemical analyzer (LBA) to determine whether the POC meter would be reliable for on-farm measurement of blood glucose and BHB concentrations in sheep in various environmental conditions and nutritional states. Animals-36 pregnant mixed-breed ewes involved in a maternal feed restriction study. Procedures-Blood samples were collected from each sheep at multiple points throughout gestation and lactation to allow for tracking of gradually increasing metabolic hardship. Whole blood glucose and BHB concentrations were measured with the POC meter and compared with serum results obtained with an LBA. Results-464 samples were collected. Whole blood BHB concentrations measured with the POC meter compared well with LBA results, and error grid analysis showed the POC values were acceptable. Whole blood glucose concentrations measured with the POC meter had more variation, compared with LBA values, over the glucose ranges evaluated. Results of error grid analysis of POC-measured glucose concentrations were not acceptable, indicating errors likely to result in needless treatment with glucose or other supplemental energy sources in normoglycemic sheep. Conclusions and Clinical Relevance-The POC meter was user-friendly and performed well across a wide range of conditions. The meter was adequate for detection of pregnancy toxemia in sheep via whole blood BHB concentration. Results should be interpreted with caution when the POC meter is used to measure blood glucose concentrations.
Afficher plus [+] Moins [-]Evaluation of serum trace mineral, vitamin D, and sex steroid hormone concentration, and survey data in llamas and alpacas with metacarpophalangeal and metatarsophalangeal hyperextension
2013
Semevolos, Stacy A. | Reed, Shannon K. | Schultz, Loren G.
Objective: To characterize serum trace mineral, sex steroid hormone, and vitamin D concentrations and identify factors associated with metacarpophalangeal and metatarsophalangeal hyperextension in llamas and alpacas. Samples: Serum samples from 79 llamas and 15 alpacas and owner survey data for 573 llamas and 399 alpacas. Procedures: Serum samples were stored at −20°C until analysis and were evaluated for trace mineral, vitamin D, estradiol, progesterone, and testosterone concentrations. Information regarding age of onset, number of affected animals in herd, feed and supplements given, type of housing, and management practices was obtained in an owner survey. Results: Higher serum zinc and iron concentrations were associated with metacarpophalangeal and metatarsophalangeal hyperextension in camelids, compared with controls. In summer and fall months, vitamin D concentrations were significantly higher in affected camelids than controls. Overall prevalence was 13.3% in llamas, compared with 0.7% in alpacas. No management factors were found to be predictive of this condition. No other factors examined were associated with metacarpophalangeal and metatarsophalangeal hyperextension. Conclusions and Clinical Relevance: Despite similar supplementation practices and environmental conditions between affected and unaffected animals, an association of high serum zinc, iron, and vitamin D concentrations in affected camelids, compared with controls, may indicate differences of intake or absorption of dietary supplements.
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